Scaffold.



UNITED STATES PATENT OFFICE.

SAMUEL RASHKOVSKY, OF ST. LOUIS, MISSOURI.

SGAFFOLD.

To all whom it may concern:

Be it known that I, SAMUEL RAsnKovsKY, a citizen of the United States,residing at St. Louis, Missouri, have invented a certain new and usefulImprovement in Scaifolds, of which the following is a full, clear, andexact description, such as will enable-others skilled in the art towhich it appertains to make and use the same.

This invention relates to scaffolds such as are erected on the outsideof a building to form a supporting platform for workmen who are engagedin work on the exterior of the building.

One object of my invention is to provide an adjustable scaffold in whichthe vertically-disposed member or members that sustain the platform orstaging are each made up of a plurality of rack-toothed bars that areconnected together in a novel manner.

Another object is to provide a strong and substantial adjustablescaffold that can be changed easily for use on high or low buildings,and which can be stored compactly when it is not in use. And stillanother object is to provide a safe scaffold which is so designed thatthe platform or staging can be raised and lowered easily and lockedsecurely in adjusted position by the workmen on the platform.

Other objects and desirable features of my invention will be hereinafterpointed out.

Figure 1 of the drawings is a side elevational view of an adjustablescaffold constructed in accordance with my invention; Fig. 2 is a frontelevational view of one of the vertically-disposed sectional tracks andthe adjustable carriage on same which supports one end of the platformor staging; Fig. 3 is a detail horizontal sectional view taken on theline 3-8 of Fig. 2; and Fig. 4 is a detail horizontal sectional viewtaken on the line l-4 of Fig. 1.

Referring to the drawings which illustrate the preferred form of myinvention, A designates a plurality of rack-toothed bars that areconnected together so as to form a vertically-disposed track which issuspended in some suitable manner from the roof or cornice of thebuilding, as, for example, by means of hooks 1. I have herein shown onlyone of said tracks and the traveling carriage on said track thatsupports the staging or platform; but it will of course be understood,that, in practice, two of said tracks and carriages are used whenever acompara:

Specification of Letters Patent.

Application filed March 1, 1913.

Patented June 23, 1914. Serial No. 751,439.

tively long staging or platform is provided for the workmen to stand on.The racktoo-thed bars or members A preferably consist of thin strips ofsteel provided on one edge with teeth 2 and having their ends joinedtogether by means of C-links 3 that pass through holes in said bars andwhich are disposed at approximately right angles to the bars so thatthey project laterally from the sides of same, as shown clearly in Fig.1, thus forming a long sectional track on which the platform-sustainingcarriage travels. The links 3 are preferably provided with openings, asshown in Fig. 1, so as to permit the bars and links to be connected anddisconnected easily. The platform-sustaining carriage herein shown iscomposed of two angle bars 1 that are tied together bytransversely-disposed braces which are so designed that they act asguides for the vertically-disposed track on which the carriage travels.The brace or tie member at the upper ends of the bars 4 preferablyconsists of a casting 5 in which a pinion 6 is journaled, as shown inFigs. 2 and 3, so as to mesh with the teeth 2 on the rack-bars A andthus cause the carriage to move vertically on the track when the pinion6 is rotated, said pinion being provided with a crank arm or handle 7that can be actuated by a workman standing on the platform or staging B,indicated. by broken lines in Figs. 1 and 2. The tie member 5 isprovided with a guiding portion 8 through which the racktoothed bars Apass, and said guiding portion 8 is so formed that the C-links 3 thatconnect the rack-bars A together can travel through same, the guidingportion 8 of the casting 5 at the upper end of the carriage beingprovided at one side with a slot 8 and at its opposite side with arecess 8 which is arranged diametrically opposite the slot 8 as shown inFig. 3. The transversely-disposed brace or tie member 9 that isconnected to the angle bars 1 intermediate the ends of same, is providedwith a similar guiding portion 9 for the rack-toothed bars A and C-links3, and the lower ends of the angle-bars 4 are tied together by atransversly-disposed brace or tie member 10 of similar construction tothe members 5 and 9 previously described, the tie member 10 being shownclearly in Fig. 4E.

The vertically-disposed track and the carriage that travels thereon areheld away from the side of the building by means of a brace C at thelower end of the carriage which is provided with one or more rollers 11that bear against the outer face of the Wall of the building, as shownin Figs. 1 and at. The brace C herein shown is adjustably connected tothe platform-sustaining carriage, and preferably consists of a bar, bentto form two side legs 01' portions 12 that embrace the tie member 10 atthe lower end of the carriage, said tie member 10 being preferablyprovided with guides 10 through which the side legs 12 of the brace Opass. Any suitable means may be employed for securing the brace C to thecarriage, the means herein shown consisting of wing-bolts 18 on theguides 10 that pass through holes 14 in the side legs 12 of the brace.As shown in Figs. 1 and a the side legs of the brace C have a pluralityof holes 14 so as to provide for the lateral adjustment of said brace,and said side legs 12 are made long enough so that they will project asufiicient distance beyond the opposite side of the carriage to form asubstantial support for the staging or platform B on which the workmenstand.

Means is provided for locking the carriage in adjusted position, and inthe embodiment of my invention herein shown said means consists of a dog15 pivotally connected to the intermediate tie member 9 on the carriageand provided with a tooth 15"* that cooperates with the teeth of therack-bars A. A leaf-spring 16 that is connected to the carriage tends toforce said locking dog into engagement with the rackbars, and a catch 17is provided for holding said locking dog either in an operative orinoperative position, the catch 17 being pivotally mounted on a bracket18 on the carriage and adapted to cooperate with one of a pair ofnotches 19 in a laterally projecting arm on the locking dog 15, as shownin Fig. 2.

l/Vhen it is desired to raise or lower the platform B on which theworkmen are standing the workmen move the locking dogs 15 of bothcarriages into an inoperative position and then rotate the pinions 6 onsaid carriages in the proper direction, the rotary movement of saidpinions causing the carriages to move vertically with relation to therack-toothed bars A that form the tracks for the carriages. The bars Acan be connected together easily so as to lengthen or shorten thetracks, and when the scaffold is not in use it can be stored in a smallspace owing to the compactness of the carriage and of the flat bars Athat form the track.

Such a scaffold can be modified easily so as to enable it to be used oneither a high or a low building; the supporting platform B on whichthe'workmen rest can be adjusted toward or away from the wall of thebuilding by simply changing the adjustment of the brace C; the scaffoldis perfectly safe and is capable of supporting a great load, and onaccount of its simple construction it can be manufactured and marketedat a low cost.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a scaffold, a vertically disposed track suspended from asustaining member and made up of a plurality of flat metal bars havingrack teeth formed on one edge of same, substantially C-shaped links forconnecting said bars together, said links being disposed atapproximately right angles to said bars and having openings which permitthe bars and links to be connected and disconnected easily, a carriagearranged to travel vertically on said track and provided with guideswhich emb ace the opposite sides of the track, said guides havingopenings or spaces so as to provide a clearance for the links thatconnect the bars together, a manually-operated pinion 011 said carriagethat meshes with the rack teeth on said track bars and thus causes thecarriage to travel vertically when the pinion is rotated, and means onsaid carriage for sustaining a platform and for holding the carriage andtrack spaced away from the wall of the building on which the scaffold isused.

2. In a scaffold, a vertically disposed track suspended from asustaining member and made up of a plurality of flat metal bars havingrack teeth formed on one edge of the same, substantially C-shaped linksfor connecting said bars together, said links being disposed atapproximately right angles to said bars and having openings which permitthe bars and links to be connected and disconnected easily, a carriagearranged to travel vertically on said track and provided with guideswhich embrace the opposite sides of the track, said guides havingopenings or spaces so as to provide a clearance for the links thatconnect the bars together, a manually-operated pinion on said carriagethat meshes with the rack teeth on said track bars and thus causes thecarriage to travel vertically when the pinion is rotated, means on saidcarriage for sustaining a platform and for holding the carriage andtrack spaced away from the wall of the building on which the scaffold isused, means on the carriage for locking the carriage to the track, andmeans for enabling the carriage and track to be adjusted toward and awayfrom the wall of the building.

3. In a scaffold, a relatively long and narrow vertically-disposedcarriage provided on one side with guides, a vertically disposed trackpassing through said guides and having its upper ends suspended from asustaining member, said track being made up of a plurality of flatstrips of metal joined together by links that are disposed at rightangles to the strips, rack teeth formed in one edge of said strips, ahousing on the guide at the upper end of the carriage, amanually-operated pinion journaled in said housing and meshing with theteeth on the strips that constitute the track, and a wallengaging braceat the lower end of the carriage provided with an outwardly projectingportion for sustaining a platform.

4. In a scaffold, a relatively long and narrow vertically disposedcarriage which is substantially channel-shaped in cross section, guidesextending transversely of the web of said carriage, a verticallydisposed track passing through said guides and having its upper endssuspended from a sustaining member, said track being made up of aplurality of flat metal bars arranged parallel to the web of thecarriage and detachably connected together by substantially C- shapedlinks disposed at right angles to the bars, the guides on the carriagebeing so shaped that said links can pass through same easily, a pinionon said carriage that meshes with rack teeth formed in the edges of saidtrack bars, a locking device on the carriage that cooperates with saidrack teeth to hold the carriage in adjusted position, a wall brace atthe lower end of the carriage that embraces same and projects forwardlyfrom the carriage so as to sustain the platform of the scaffold, guideson the carriage through which the side portions of said wall brace pass,and means for adjustably-connecting said wall brace to the carriage.

In testimony whereof I hereunto affix my signature in the presence oftwo witnesses, this twenty fifth day of February 1913.

SAMUEL RASHKOVSKY.

.lVitnesses WELLS L. CHURCH, GEORGE BAKEWELL.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of I'atents. Washington, D. G.

